ok reyk@ but we should think about putting it in all copies of kroute.c
On Thu, Apr 21, 2011 at 01:24:36PM +0100, Stuart Henderson wrote:
> Diff below adds a "filter-routes" option, defaulting to "no".
> "yesno" borrowed from bgpd's parser.
>
> I've been using a similar diff (but without the config option)
> for a while on my BGP routers where I want to monitor interface
> information via SNMP but don't care about fetching the routing
> table that way.
>
> It seriously reduces CPU time when a major peer bounces (or
> when bgp is coming back up after the rde eats all available
> ram and crashes).
>
> PID USERNAME PRI NICE SIZE RES STATE WAIT TIME CPU COMMAND
> 7565 _bgpd 2 0 123M 124M sleep/1 poll 0:44 28.22% bgpd:
> route decision engine
> 30322 _snmpd 2 0 20M 21M sleep/0 kqread 0:06 10.89% snmpd:
> snmp engine
> 18490 root 2 0 20M 21M sleep/0 poll 0:20 9.77% bgpd:
> parent
> 23183 _bgpd 2 0 948K 1480K sleep/0 poll 0:05 1.71% bgpd:
> session engine
>
> Any comments? ok?
>
> Index: kroute.c
> ===================================================================
> RCS file: /cvs/src/usr.sbin/snmpd/kroute.c,v
> retrieving revision 1.16
> diff -u -p -r1.16 kroute.c
> --- kroute.c 7 Mar 2011 07:43:02 -0000 1.16
> +++ kroute.c 21 Apr 2011 12:15:41 -0000
> @@ -45,6 +45,8 @@
>
> #include "snmpd.h"
>
> +extern struct snmpd *env;
> +
> struct {
> struct event ks_ev;
> u_long ks_iflastchange;
> @@ -159,6 +161,10 @@ kr_init(void)
> if (setsockopt(kr_state.ks_fd, SOL_SOCKET, SO_USELOOPBACK,
> &opt, sizeof(opt)) == -1)
> log_warn("kr_init: setsockopt"); /* not fatal */
> +
> + if (env->sc_rtfilter && setsockopt(kr_state.ks_fd, PF_ROUTE,
> + ROUTE_MSGFILTER, &env->sc_rtfilter, sizeof(env->sc_rtfilter)) == -1)
> + log_warn("kr_init: setsockopt(ROUTE_MSGFILTER)");
>
> /* grow receive buffer, don't wanna miss messages */
> optlen = sizeof(default_rcvbuf);
> Index: parse.y
> ===================================================================
> RCS file: /cvs/src/usr.sbin/snmpd/parse.y,v
> retrieving revision 1.19
> diff -u -p -r1.19 parse.y
> --- parse.y 18 Oct 2010 13:29:49 -0000 1.19
> +++ parse.y 21 Apr 2011 12:15:41 -0000
> @@ -112,13 +112,13 @@ typedef struct {
>
> %token INCLUDE
> %token LISTEN ON
> -%token SYSTEM CONTACT DESCR LOCATION NAME OBJECTID SERVICES
> +%token SYSTEM CONTACT DESCR LOCATION NAME OBJECTID SERVICES RTFILTER
> %token READONLY READWRITE OCTETSTRING INTEGER COMMUNITY TRAP RECEIVER
> %token ERROR
> %token <v.string> STRING
> %token <v.number> NUMBER
> %type <v.string> hostcmn
> -%type <v.number> optwrite
> +%type <v.number> optwrite yesno
> %type <v.data> objtype
> %type <v.oid> oid hostoid
>
> @@ -157,6 +157,21 @@ varset : STRING '=' STRING {
> }
> ;
>
> +yesno : STRING {
> + if (!strcmp($1, "yes"))
> + $$ = 1;
> + else if (!strcmp($1, "no"))
> + $$ = 0;
> + else {
> + yyerror("syntax error, "
> + "either yes or no expected");
> + free($1);
> + YYERROR;
> + }
> + free($1);
> + }
> + ;
> +
> main : LISTEN ON STRING {
> struct addresslist al;
> struct address *h;
> @@ -212,6 +227,15 @@ main : LISTEN ON STRING {
> } host {
> hlist = NULL;
> }
> + | RTFILTER yesno {
> + if ($2 == 1)
> + conf->sc_rtfilter = ROUTE_FILTER(RTM_NEWADDR) |
> + ROUTE_FILTER(RTM_DELADDR) |
> + ROUTE_FILTER(RTM_IFINFO) |
> + ROUTE_FILTER(RTM_IFANNOUNCE);
> + else
> + conf->sc_rtfilter = 0;
> + }
> ;
>
> system : SYSTEM sysmib
> @@ -378,6 +402,7 @@ lookup(char *s)
> { "community", COMMUNITY },
> { "contact", CONTACT },
> { "description", DESCR },
> + { "filter-routes", RTFILTER },
> { "include", INCLUDE },
> { "integer", INTEGER },
> { "listen", LISTEN },
> Index: snmpd.conf.5
> ===================================================================
> RCS file: /cvs/src/usr.sbin/snmpd/snmpd.conf.5,v
> retrieving revision 1.13
> diff -u -p -r1.13 snmpd.conf.5
> --- snmpd.conf.5 18 Jul 2010 08:03:04 -0000 1.13
> +++ snmpd.conf.5 21 Apr 2011 12:15:41 -0000
> @@ -85,6 +85,18 @@ Specify the name of the read-write commu
> The default value is
> .Ar private .
> .Pp
> +.It Xo
> +.Ic filter-routes
> +.Pq Ic yes Ns \&| Ns Ic no
> +.Xc
> +If set to
> +.Ic yes ,
> +ask the kernel to filter route update messages on the routing socket.
> +Routing table information will not be available, but CPU use will be
> +reduced during bulk updates.
> +The default is
> +.Ic no .
> +.Pp
> .It Ic system contact Ar string
> Specify the name or description of the system contact, typically a
> name or an e-mail address.
> Index: snmpd.h
> ===================================================================
> RCS file: /cvs/src/usr.sbin/snmpd/snmpd.h,v
> retrieving revision 1.30
> diff -u -p -r1.30 snmpd.h
> --- snmpd.h 20 Sep 2010 08:56:16 -0000 1.30
> +++ snmpd.h 21 Apr 2011 12:15:41 -0000
> @@ -303,6 +303,7 @@ struct snmpd {
>
> int sc_ncpu;
> int64_t *sc_cpustates;
> + int sc_rtfilter;
> };
>
> /* control.c */
